Python doesn't retrieve data from mysql table - mysql

Question

I am tried to retrieve entry_time from mysql table (named user) and then find the time difference between now (exitTime) and the entry_time. My code doesn't seem to recover the data from mysql table. f is the id search key for the code which searches against the ID (PRIMARY KEY) of the mysql database to find the corresponding entry_time.
I have tried taking it as a string as well to see if i could retrieve the value but to no avail.
from tkinter import *
import time,datetime
import mysql.connector as mc
from tkinter import messagebox
import cv2
import matplotlib.pyplot as plt
import sys
import time
def billCalc():
global exitTime
global EntryTime
EntryTime = datetime.datetime
exitTime = datetime.datetime.now()
try:
conn = mc.connect(host='localhost', user='root', password='', db='car_park_master')
except mc.Error as e:
print("Error %d: %s" % (e.args[0], e.args[1]))
sys.exit(1)
sql_Query = "SELECT `entry_time` FROM `user` WHERE `ID` ="+f.get()
#id = (f.get(),)
print(record[1])
cursor = conn.cursor(buffered=True)
cursor.execute(sql_Query, id)
record = cursor.fetchone()
# selecting column value into varible
EntryTime = datetime(record[1])
print(record[1])
conn.close()
print(exitTime)
print(EntryTime)
print(f.get())
BillTime = EntryTime - exitTime
Bill = BillTime * 2
print(Bill.get())
def main_screen():
screen = Tk()
screen.geometry("300x400")
screen.title("EXIT GATE")
global f
f = StringVar()
Entry(screen, textvariable=f).place(x=150, y=200)
print(f.get())
Button(screen,text="Exit",height='2',width='15',command=billCalc).place(x=150,y=300)
screen.mainloop()
main_screen()
It is supposed to take an exit time using datetime.datetime.now() which it does.
Then it is supposed to take input ID from the user to search in the database.
After that it is supposed to retrieve the corresponding entry time
Find the difference between entrytime and exit time in seconds
Then provide a bill.
EDITED AND FIXED CODE:
from tkinter import *
import datetime
import mysql.connector as mc
from tkinter import messagebox
import cv2
import matplotlib.pyplot as plt
import sys
import time
def billCalc():
global exitTime
global EntryTime
EntryTime = datetime.datetime
exitTime = datetime.datetime.now()
try:
conn = mc.connect(host='localhost', user='root', password='', db='car_park_master')
except mc.Error as e:
print("Error %d: %s" % (e.args[0], e.args[1]))
sys.exit(1)
cursor = conn.cursor()
cursor.execute("SELECT entry_time FROM user where id="+f.get())
record = cursor.fetchone()
EntryTime = (record[0])
conn.close()
print(exitTime)
print(EntryTime)
print(f.get())
BillTime = exitTime - EntryTime
print(BillTime)
def main_screen():
screen = Tk()
screen.geometry("300x400")
screen.title("EXIT GATE")
global f
f = StringVar()
Entry(screen, textvariable=f).place(x=150, y=200)
print(f.get())
Button(screen,text="Exit",height='2',width='15',command=billCalc).place(x=150,y=300)
screen.mainloop()
main_screen()